Radiometric dating of rock strata
Most scientists and many Christians believe that the radiometric dating methods prove that the earth is 4.5 billion years old.
Even the use of isochron dating, which is supposed to eliminate some initial condition assumptions, produces dates that are not reliable.
Some of the common isotope pairs used are K-Ar, Rb-Sr, Pb-Pb, and U-Pb.
Carbon-14 dating is another common technique, but it can only be used on carbon-containing things that were once alive.
The claimed “fact” that decay rates have always been constant is actually an inference based on a uniformitarian assumption.
It is true that radioisotope decay rates are stable today and are not largely affected by external conditions like change in temperature and pressure, but that does not mean that the rate has always been constant.The reason this age may not be a true age—even though it is commonly called an absolute age—is that it is based on several crucial assumptions.